1. Field of Invention
This invention relates to telecommunications equipment systems, and specifically to an apparatus for providing air flow in a card based telecommunications equipment assembly.
2. Relevant Art
Most modern telecommunications equipment contains electronic apparatuses mounted in a chassis (also referred to as xe2x80x9cshelfxe2x80x9d). The chassis is generally enclosed, with a front access door, side walls, and a backplane. The chassis is enclosed to prevent stray material from entering the casing and damaging the electronic apparatus and to prevent stray emission of electromagnetic energy. Typically, the electronic apparatus housed inside the chassis includes heat generating components. Most heat generating components must not be allowed to overheat or else they may lose their effectiveness. Thus, it becomes necessary to provide for the cooling of components within the chassis.
Typically, components are cooled using air that is forced into the chassis and made to flow over the components. Conventional fan trays are typically employed to force the air through the chassis. For example, in a conventional push-pull air flow system, a fan tray is positioned at a bottom part of the chassis with an inlet opening while a second fan tray is positioned at the top part of the chassis with an exhaust opening. Unfortunately, due to the density in today""s telecommunications products, the push-pull air flow system uses valuable space, which could otherwise be used for fiber routing.
The present invention provides a high efficiency multi-directional airflow system for a telecommunications equipment assembly used for housing electronic apparatuses which facilitate telecommunications functionality. In accordance with the present invention, the equipment assembly defines an internal cavity which can be divided into a plurality of air flow channels. Each of the plurality of air flow channels captures a sub-portion of the overall volume provided by the internal cavity. The smaller volume flow channels provide a smaller cross-sectional area through which the majority of air travels. Since the cross-sectional area is smaller, the velocity of the air through the flow channels is increased. Since the air velocity is increased, the heat transfer coefficient is also increased, thus allowing for the more efficient removal of heat from the electronic apparatuses.
In accordance with the present invention, a set of fan trays can be used to achieve push-pull air flow through the channels. The single set of fan trays can include a plurality of fans each directionally positioned to work in series to cause air to flow through the plurality of flow channels. Advantageously, the single set of fan trays can be positioned on the same side of the equipment assembly, which allows the use of the same area for inlet and exhaust of the cooling air to increase the amount of vertical space used for routing fibers.
In one aspect of the present invention, a telecommunications equipment assembly is provided, which includes a chassis defining an internal cavity for receiving a plurality of electronic apparatus. The assembly also includes at least one divider mechanism coupled to each of the plurality of electronic apparatus, where the divider mechanisms define at least two flow channels within the internal cavity. The assembly further includes a first fan tray configured to cause air to flow through the first flow channel; and a second fan tray configured to cause the air flowing in the first channel to flow through the second flow channel. The first fan tray and the second fan tray are positioned on an area at the first end of the chassis.
In another aspect of the invention, a telecommunications equipment assembly is provided. The assembly includes a chassis defining an internal cavity for receiving a plurality of electronic apparatuses. The assembly also includes a means for defining a plurality of flow channels within the internal cavity; and a first fan placed in series with a second fan to pull air into the plurality of flow channels and to push air out from the plurality of flow channels. The first fan and the second fan are positioned on an area proximate to the same portion of the chassis.
In another aspect of the present invention a method is provided for providing air flow through a telecommunications equipment assembly. The method includes providing a chassis including an internal cavity; dividing the internal cavity into a plurality of flow channels, where the flow channels include a first end and a second end; and pulling and pushing air through the flow channels.
In yet another aspect of the present invention, a telecommunications equipment assembly is provided which includes a chassis having a first surface and which defines an internal cavity. The assembly also includes a means for dividing the internal cavity into a plurality of flow channels, and a means for pulling and pushing air through the flow channels. The means being combined on a first surface of the chassis.
The present invention provides many advantages over conventional air flow systems. For example, the use of fans in series provides a reduction in back pressure acting on each fan, which prolongs the life of each fan. The higher air velocity generated by the present invention provides for more efficient cooling due to an increase in the heat transfer coefficient. The present invention, also provides a more consistent temperature rise when used in a rack mount multi-shelve system. Because of the more efficient heat transfer capability, a higher degree of fan failure can be tolerated in the system. Since the exhaust and intake are positioned using the same area, less openings in the equipment assembly are required, thus substantially reducing the potential for unwanted EMI emission.
These and other objects, features and advantages of the present invention will be more readily apparent from the detailed description of the preferred embodiments set forth below taken in conjunction with the accompanying drawings.